"Julien was great," said a disappointed Federer afterwards. "He created more chances than me. I did everything I could, but he deserved to win."

Federer had won 28 consecutive quarterfinals against players ranked outside of the ATP's top 20, but the World No. 39 looked to have his number early and often over the course of the evening.

Benneteau was aggressive from the start, breaking Federer in the first game, and even though Federer drew level with a break back, the Frenchman kept up the pressure and regained the lead in the seventh game.

In the second set, Benneteau appeared to be on his way to a surprisingly easy victory when he broke for a 3-1 as a Federer forehand sailed harmlessly long.

But Federer showed signs of life down the stretch. Even as his unusually poor serving continued to hamper him, he was still able to break the Frenchman to love to get back on serve at 3-4.

In the next game, Federer fell behind 0-30, but rallied to win the next four points to bring the set square at 4-all.

After squandering chances to break for a 6-5 lead, Federer then found himself under the gun as he served to force a tiebreaker. On a day where Federer would only manage to win an uncharacteristically low 33 percent of second serve points, Federer double-faulted to give Benneteau a match point.

It was all the window the Frenchman needed. After a rollicking rally Federer's attempt at a backhand winner into the open court missed the line by a touch and Benneteau had secured the milestone win.

"This is one of my biggest wins, for sure," he said afterwards.

Federer, who had been unbroken in first two matches in Rotterdam, was only able to save three of eight break point chances he faced on the evening. "When you get broken as much as happened to me," he said "you won't get the job done."

Dimitrov won a spirited three-set battle with Marcos Baghdatis, 6-7(4), 7-6(0), 6-3. The World No. 41 went on an 18-point run to close out the second set and take the advantage in the third to reach his second semifinal of 2013.

"I definitely had to fight with myself in the second set, I lost focus a little bit," the 21-year-old said. "The match went through a lot of phases and I was happy I got out of it."